Options for babel transpiling.


babel.transform(code, options);
$ babel --name=value


Option Default Description
filename "unknown" Filename for use in errors etc.
filenameRelative (filename) Filename relative to sourceRoot.
presets [] List of presets (a set of plugins) to load and use.
plugins [] List of plugins to load and use.
highlightCode true ANSI highlight syntax error code frames
only null A glob, regex, or mixed array of both, matching paths to only compile. Can also be an array of arrays containing paths to explicitly match. When attempting to compile a non-matching file it's returned verbatim.
ignore null Opposite to the only option.
auxiliaryCommentBefore null Attach a comment before all non-user injected code.
auxiliaryCommentAfter null Attach a comment after all non-user injected code.
sourceMaps false If truthy, adds a map property to returned output. If set to "inline", a comment with a sourceMappingURL directive is added to the bottom of the returned code. If set to "both" then a map property is returned as well as a source map comment appended.
inputSourceMap null A source map object that the output source map will be based on.
sourceMapTarget (filenameRelative) Set file on returned source map.
sourceFileName (filenameRelative) Set sources[0] on returned source map.
sourceRoot (moduleRoot) The root from which all sources are relative.
moduleRoot (sourceRoot) Optional prefix for the AMD module formatter that will be prepend to the filename on module definitions.
moduleIds false If truthy, insert an explicit id for modules. By default, all modules are anonymous. (Not available for common modules)
moduleId null Specify a custom name for module ids.
getModuleId null Specify a custom callback to generate a module id with. Called as getModuleId(moduleName). If falsy value is returned then the generated module id is used.
resolveModuleSource null Resolve a module source ie. import "SOURCE"; to a custom value. Called as resolveModuleSource(source, filename).
code true Enable code generation
babelrc true Specify whether or not to use .babelrc and .babelignore files.
ast true Include the AST in the returned object
compact "auto" Do not include superfluous whitespace characters and line terminators. When set to "auto" compact is set to true on input sizes of >100KB.
comments true Output comments in generated output.
shouldPrintComment null An optional callback that controls whether a comment should be output or not. Called as shouldPrintComment(commentContents). NOTE: This overrides the comment option when used.
env {}

This is an object of keys that represent different environments. For example, you may have:

{ env: { production: { /* specific options */ } } }`

which will use those options when the enviroment variable BABEL_ENV is set to "production". If BABEL_ENV isn't set then NODE_ENV will be used, if it's not set then it defaults to "development"

retainLines false

Retain line numbers. This will lead to wacky code but is handy for scenarios where you can't use source maps.

NOTE: This will obviously not retain the columns.
extends null A path to an .babelrc file to extend